The present invention relates to a vehicle seat assembly having a child seat integrated into a seat back which is in turn rotatably mounted in the vehicle and in particular to an interlock between the integral child seat assembly and a latch for the rotating seat back.
Many vehicle seat assemblies, such as bench seats in a van or multi-purpose passenger vehicle and the rear seats in certain passenger cars, are equipped with seat backs that are rotatable between an upright use position and horizontal storage position. The rotating rear seat back is provided in passenger cars to expand the trunk capacity of the vehicle into the rear seat area. In vans, a folding seat back enables larger items to be carried in the van on top of the seats and reduces the storage space required for a removable seat when the seat has been removed from the vehicle. The rotating seat back includes a latch mechanism to hold the seat back in its upright use position. In a van bench seat, the latch is typically at one or both sides of the seat assembly near the seat back pivot axis. In a passenger car seat assembly with a fold down rear seat back, the latch is typically at the top of the seat back and secures the seat back to the rear sill or package shelf of the passenger car body.
Many seat assemblies have been developed which include an integral child seat that enables an infant or small child to be safely carried in the vehicle without the need for a separate child seat. Integral child seats typically include a child seat cushion panel rotatably mounted to the seat back of a seat assembly. In a stowed position, the child seat cushion panel forms a portion of the adult seat back. When the child seat is deployed, the child seat cushion panel forms a horizontal seat cushion for a child occupant. Additional components of the child seat may also be included in the seat back.
The integral child seat also includes a separate restraint system for the child. The separate child restraint system is generally a three or five point belt restraint. In many cases, at least a portion of the loads from all or some of the restraint system belts are transferred to the seat back frame and from there to the vehicle body structure. When a child seat is integrated into a folding seat back, the child seat restraint loads are transferred from the seat back frame to the vehicle body through the seat back latch. It is thus necessary to ensure that the child seat is not used unless the seat back is properly latched in its upright use position.
Interlock mechanisms have been developed which couple the seat back latch to the child seat. The interlock mechanism prevents deployment of the child seat when the seat back is unlatched and prevents unlatching of the seat back when the child seat is deployed. One type of interlock mechanism includes a latch for holding the child seat cushion panel in a stowed position. The child seat latch includes a latch striker bar mounted to the child seat cushion panel. Other types of interlock mechanisms have been developed which use a number of cams and levers at each end of a pull cable to connect the seat back latch to the child seat cushion panel. One such interlock pulls on the cable upon deployment of the child seat and adds a cam to the seat back latch to prevent release of the seat back when the child seat is deployed. This requires extensive modification of the seat back latch.
It is an object of the present invention to provide an interlock mechanism which avoids the need for a latch striker on the child seat cushion panel and which minimizes the number of separate components i.e., cams and levers, in the interlock mechanism.
In addition, since seat back latches have been previously developed without an interlock mechanism, it is a further object of the invention to minimize the redesign of the seat back latch in providing the interlock mechanism.
It is another object of the invention to provide an interlock mechanism in the form of a subassembly which can be easily installed during assembly of the seat back. This reduces the number of separate components that need to be added to the seat back frame when the child seat option is desired.
The seat assembly of the present invention, with a folding seat back and an integral child seat within the seat back, includes an interlock between the seat back latch and the integral child seat which operates at the pivot point of the child seat cushion panel. By locking the child seat cushion at the pivot point, the need for a striker positioned on the child seat cushion panel is eliminated. The interlock includes a cable connected at one end to a moving component of the seat back latch and connected at the other end to a pivoting lock member adjacent to the child seat cushion panel pivot. The lock member either directly engages the moving hinge of the child seat cushion panel or engages a pawl which in turn engages the hinge. In an alternative embodiment, a pawl engages a sector fixed to the child seat cushion panel pivot shaft to prevent the shaft from rotating.
By attaching the pull cable to an existing moving component of the seat back latch, for pulling of the cable upon latch release, minimal redesign of the seat back latch is required. The cable is pulled by operation of the seat back latch to move the lock member at the child seat cushion panel pivot. This configuration reduces the number of components in the interlock mechanism to a minimum compared to prior interlock mechanisms. The result is a low cost interlock mechanism which, due to the small number of components, is simple and easy to assemble.
At the child seat cushion panel pivot, the interlock mechanism is contained within a housing as a subassembly that is mounted to the seat back frame. In one embodiment, the housing actually forms the pivot attachment for the child seat cushion panel at one side. With a similar hinge only housing on the other side, the only frame modifications needed for the child seat option are the addition of two housings. In another embodiments the child seat cushion panel pivot shaft extends into the housing and is coupled to the interlock mechanism.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.